The specific aims of this proposed Phase II research program are: 1. To complete the development of the System for evaluating patient support systems fy measuring the distribution for critical regions of the body. 2. To clinically validate the "measuring system" and establish its performance int he evaluation and development of truly effective support systems to treat patients with pre-existing pressure ulcers and prevent pressure ulcer formation of patients at risk of their formation. This system is intended to provide a truly standard testing system for the evaluation of the pressure and shear properties of various mattresses, bed support systems, overlays and other constructions for the reduction of interface pressure and shear on patients at risk of developing pressure ulcers for the reduction of interface pressure and shear on patients at risk of developing pressure ulcers. The commercial availability of a clinically validated "measuring system" will provide a quantitative standard for the testing and development of patient support systems, which does not now exist, and which will lead to improved patient support systems. PROPOSED COMMERCIAL APPLICATION: The "measuring System" to be demonstrated in this Phase II program will provide a quantitative standard to rank patient support systems and develop better ones.